After recently drifting into recreational circles due to its hallucinogenic properties, ketamine is now being re-evaluated among medial researchers for its powerful anti-depressant qualities. A new study has now revealed the drug can be effective in rapidly reducing suicidal thoughts in patients.

For the last decade a vanguard of scientists has been researching the unexpected anti-depressant effects of ketamine, an old drug initially developed as an anesthetic in the 1960s. The rapid anti-depressant effects of ketamine have been so anecdotally strong that a number of "ketamine clinics" have popped up in the US to deliver the drug to patients, for a price.

This new study, from Columbia University Medical Center, homes in on the drug's rapid anti-depressant qualities, and examines its effects on patients with acute suicidal thoughts. It is the first study to focus explicitly on suicidal patients, as opposed to prior studies that have looked at more general depression symptoms.

"Currently available antidepressants can be effective in reducing suicidal thoughts in patients with depression, but they can take weeks to have an effect," explains study leader Michael Grunebaum. "Suicidal, depressed patients need treatments that are rapidly effective in reducing suicidal thoughts when they are at highest risk. Currently, there is no such treatment for rapid relief of suicidal thoughts in depressed patients."

The study took 80 patients with "clinically significant suicidal thoughts" and assigned them either a low-dose infusion of ketamine or a sedative called midazolam, commonly prescribed to reduce acute suicidal thoughts in at-risk patients. Twenty-four hours after the infusion the ketamine group displayed a major improvement in the reduction of suicidal thoughts compared to the midazolam group.

Perhaps the most compelling part of the study was the six-week follow up showing that the effects of the ketamine seemed to hold strong for an extended duration. The ketamine group reported an overall improvement in mood, depression and fatigue, indicating the drug had a major anti-depression effect as well as a rapid effect on reducing suicidal thoughts.

"This study shows that ketamine offers promise as a rapidly acting treatment for reducing suicidal thoughts in patients with depression," says Grunebaum. "Additional research to evaluate ketamine's antidepressant and anti-suicidal effects may pave the way for the development of new antidepressant medications that are faster acting and have the potential to help individuals who do not respond to currently available treatments."

With several studies looking into ketamine as a viable new treatment for depression disorders this is yet another fascinating glimpse into the unexpected effects of a drug that has been used in a variety of ways, both medically and recreationally, for over half a century.

The study was published in the American Journal of Psychiatry.